Your list can be turned down for a number of reasons, most common is that you did adhear to the guide lines.
See the Listing Guidelines for more information.
Adult Sites Brand Names Content Not Found Drugs Duplicate Search Terms Finance Sites Gambling Sites Geographic Location Insufficient Content Job/Employment Terms Marketplace & Language Product Component Questionable LegalitySearcher Titles and Descriptions URLs Unacceptable Content Web Site Ownership What constitutes "substantial content"? What does not constitute "substantial content"? Zero Search Volume Terms Another reason could be because you have selected a Key Word that has a zero hit rating, this means that there have been no searches performed on this term in the past.